Flaming-arc electrode.



UNITED STATES PATENT OFFICE.

:EMILE J". GUAY, 0F LYNN, MASSACHUSETTS, ASSIGNOR T0 GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

FLAMING-ARC ELECTRODE.

Specification of Letters Batent.

Patented Aug. 6, 1912.

No Drawing. Continuation in part of application Serial No. 576,523, filed August 10, 1910. This application filed January 27, 1912. Serial No. 673,752.

Y To all whom it may concem:

Be it known that I, EMILE J. GUAY, a citizen of the United States, residing at Lynn,

It has been found that an are from an electrode in which titanium carbid is the principal light-producing constituent omits conspicuously White light and is very ellicient. Such an arc, however, is unsteady, and, in order to render it steady, I have incorporated other materials with the titanium carbid. Free carbon, calcium lluorid and cryolite, I have found to be particularly useful in steadying and generally improving the titanium carbid arc, and these materials I have added in varying proportions to the titanium carbid. Free carbon renders the electrode more conductive, while the calcium 'fluorid and cryolite fuse with the titanium carbid and carbon and maintain the amounts of carbid and'carbon that enter into the are substantially constant. In this manner the intensity of the arc is made substantially invariable. In addition to this, the calcium fluorid and carbon increase the diameter of the arc, while the cryolite adds a small amount of yellow rays to the same, which is frequently desirable.

An electrode made as above indicated, 1 have described in my prior application, No. 576,523, filed August 10, 1910, of which this application is a continuation in part. In that prior application, the .frce carbon which is added to the titanium carbid is not specifically defined, but my practice was. to use coke, and with this form of free carbon I have found that the best results are obtained when the proportions of the ingredients are as follows :-titanium carbid, 35 per cent.,calcium fluorid, 30 per cent, cryolite, 15 per cent, carbon. 20 per cent. I have also found that while when coke is -11sed as the free carbon these proportions seem to furnish the best results, small varia -tions are permissible without seriously affecting the appearance and steadiness of the arc. Thus, 1 have found that a variation of 5 per cent. either way'in the amount oftitanium .carbid and calcium fluorid and a Variation either way 'of 3 per cent. in the amount. of cryolite and carbon is permissible.

I have now discovered that by the use of a certain carbon mixture in' place of coke.

pure and simple, the resulting electrode is considerably improved; the intensity of the light emitted by the arc is rendered still more uniform and the amounts of the admixtures of titanium carbid, calcium l'luorid and cryolite can be considerably reduced and may generally be varied within a wider range than was practicable with the use of coke, pure and simple, as the free carbon constitutcnt. The carbon mixture which secures this improved result is made up by taking 20 parts of lampblack, 80 parts of finely divided coke and 25 parts of a carbonizable binding material, such as pitch. These proportions, however, may be varied considerably so long as a substantial amount of lampblack is retained. These materials are thoroughly mixed and the mixture is baked until the binder has become carbonized. The compound thus formed is then ground and constitutes the carbon mixture which in my improvement replaces the coke, pure and simple, which I have heretofore used.

With the use of the specified carbon mixture, I have made electrodes giving superior results in the following proportions of constituents:titanium carbid, 28 per cent, calcium fluorid, 24k per cent, cryolite, 10 per cent, carbon mixture, 38 per cent. From this mixture the electrode is prepared in the ordinary manner by adding to the mixture a suitable binder, squirting or molding the resulting paste into rods and baking the same until the binder becomes carbonized. I prefer to inclose the rods thus formed in a shell of carbon. This may be done by squirting the mixture into a previously prepared carbon shell; or else the rods formed of the mixture are lightly baked and are then coated with tar and again baked whereby a carbon shell or mantle is formed on its surface. It is old in the art to inclose an electrode within a carbon shell and I do not claim any novelty as to this feature.

l/Vhen my improved electrode is used with direct current, it is preferable to use it as the positive electrode and a plain carbon as be made in accordance With my invention.

' a current strength of In this manner a single lamp may he used -carbon and a predominating amount of a 8. An electrode composed or, titanium carbid, calcium fluorid, cryolite and a carbon mixture of coke, lampblack and a carbonic binder.

4:. A. "flaming arcelectrode *oantainina fia carbon mixture 0 lampblack, coke an a carbonized binder,

but when used with alternat both electrodes Will generally the negative mg current,

The permissible variations of constituents, when my improved carbon. mixture is used,- are Within Wide limits; in fact, no lower limit or the amounts-of light-giving materials can be assigned, since very small amounts of titanium carbid, calcium fiuorid and cryolite will still secure a practically constant light. The upper limit of the per. missible amounts of light-giving constituents is that quantity which with the current employed would give an excessive amount of slag, which would render the operation of the electrode unsatisfactory.

A particularadvant-age ofmy improved electrode is that it is adapted 'to be used on commercial circuits of 110 volts. The are is run at 7 5 to 80 volts, and ordinarily with from t to 6 amperes.

and a predoatm calcium fluorid' and cryolite.'

5. An electrode containing the-following constituents in substantially the following proportions :-titanium carbid, calcium fluorid, 24 per cent. 'Tcryolite, 10 per cent; and carbon, 38 per cent; carbon mixture composed of 20. pairts1ot lampblack, 80 parts (of coke 'and'the car titanium carbid, calcium lite.

"Z. A; carbon mixture for flaming arc elec-' trodes composed of lampblack, coke'and the carbonized residue of a binder.

on a 110 volt ClIC'LlItlIlStCQ-d of two in series, as is often required With electrodes otl this character, which are usually run at 40 to volts at the arc.

What it claim as new, and desire to se cure by Letters Patent of the United States 1s:-

1. An electrode composed of titanium carmy hand this 25th bid, calcium fiuorid, cryolite, and carbon.

' 2. A flaming arc electrode composed of trodes composed of 20 80 parts of coke and the'carbonized residue of 25 parts of a binder.

In witness vvhereot,-l have hereunto set day ofJanuary, 1912.

EMILE J. GUAY.

lVitnesses: 7

JOHN A. MoMA Us, J12,-

rniXture of titanium carbid, calcium fluorid FRANK G. HAQTIE.

and cryolite.

amount of: a mixture of titanium certain;

28 per cent;

6. A flaming arc electrodecontainingi'a.

bonized' residue of 25mm of. abinder, and a predominating amount ot a mixture fluorid and cryo- '8. A carbon mixtur'e for flaming are elec-' parts of l'ampbla'ck,'

all) 

